From f38c3e1c30ac53290f7d05d543ade5566f3e0026 Mon Sep 17 00:00:00 2001
From: Richard Chien <richardchienthebest@gmail.com>
Date: Fri, 21 Dec 2018 23:39:45 +0800
Subject: [PATCH] Fix command finding bug

---
 docs/changelog.md | 4 ++++
 none/command.py   | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/docs/changelog.md b/docs/changelog.md
index 4cebcffd..295e2533 100644
--- a/docs/changelog.md
+++ b/docs/changelog.md
@@ -4,6 +4,10 @@ sidebar: auto
 
 # 更新日志
 
+## next
+
+- 修复调用不存在的多级命令（例如 `/echo/nonexist`）时，抛出异常导致 WebSocket 连接断开的问题
+
 ## v0.4.3
 
 - 自然语言处理器支持响应只有机器人昵称而没有实际内容的消息，通过 `on_natural_language` 的 `allow_empty_message` 参数开启（默认关闭）
diff --git a/none/command.py b/none/command.py
index d1513631..7b8d1ea1 100644
--- a/none/command.py
+++ b/none/command.py
@@ -164,7 +164,7 @@ def _find_command(name: Union[str, CommandName_T]) -> Optional[Command]:
 
     cmd_tree = _registry
     for part in cmd_name[:-1]:
-        if part not in cmd_tree:
+        if part not in cmd_tree or not isinstance(cmd_tree[part], dict):
             return None
         cmd_tree = cmd_tree[part]